An inkjet apparatus capable of achieving a good withstand voltage in a movable part of a piezoelectric element is provided. An inkjet apparatus is provided, wherein the inkjet apparatus comprises: an actuator substrate, partitioning a cavity for accumulating ink; a vibrating film, supported by the actuator substrate and partitioning the cavity; and a piezoelectric element, on the vibrating film, and comprising an upper electrode, a lower electrode, and a piezoelectric film between the upper electrode and the lower electrode; wherein the piezoelectric film extends along a space covering the whole cavity; and the upper electrode is constrained in an inner space of the cavity.